Spray nozzle



G. L. NEELY SPRAY NOZZLE Aug. 11, 1936.

Filed Feb. '26, 1934 fi eor'g Leonard Neely INVENTOR.

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ATTORNEY v Patented Aug. 11, 1936 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to spray nozzles and particularly but notnecessarily to those in which a fluid under pressure is utilized toaspirate a liquid from a container and then atomize it to form a 5finely divided spray or mist. Such a one is dis closed in my copendingapplication Serial Number 348,164, filed March 19, 1929, and on whichPatent No. 1,948,533 issued February 27, 1934 and of which thisapplication is a continuation in part.

In small spray devices, particularly those used for atomizing liquidinsecticides by means of a pressure fluid such as water from the usualpiped supply, it is particularly diflicult to provide a simple andcheaply manufactured construction which will maintain the continuedaccurate and close alignment of the various parts forming the nozzle. Ithas been found by extensive tests that an annular converging conoidaljet of water, for example, if directed through suitable passages so noas to give it a vortical motion, will cause a reduction of pressure atits apex or converging point. If a suitable axial passage is providedfrom this apex or converging point to a liquid supply, the said liquidwill be aspirated and thoroughly mixed with the water, and the resultingmixture will be dispersed into a finely divided cone shaped spray ormist. Under some circumstances, however, it is possible to feed theliquid under a positive head, so that the aspirating action may besubsidiary 90 to the diluting, atomizing and dispersing actions.

The dimensional factors governing these actions, however, are quitecritical, particularly the thickness of the annular converging conoidaljet, the degree of vortical motion or whirling and the resulting angleof divergence of spray from the nozzle tip.

The devices heretofore utilized for maintaining these shapes andclearances have been made with two separately threaded members, theouter mem- 40 her or shell being provided with a conical recess,

and the inner member fitting into the recess and separately threadedinto the base or support member, as in my application above cited. Thusthe concentricity of the. two elements, which de- 45 termines theparallelism of the fluid passage walls has been dependent upon two setsof threads, which have been found entirely inadequate to maintain theclose tolerances, on the order of two 'or three one-thousandths of aninch, which are essential to proper operation.

Another feature which has been both difiicult and expensive to provideis the means for giving the conoidal fluid jet a whirling or vorticalmotion. Cutting helical passages or grooves in a cylindrical 55 elementis easily and quickly done, but a simultaneously helical and conicalmachining operation requires elaborate and expensive equipment.

It is an object of this invention to provide a spray nozzle in which theelements defining the conoidal converging passage may be permanently 5'and accurately fixed together during the manufacture of the nozzle.

Another object is to provide a tip for a spray nozzle in which thespacing and aligning means defining the fluid passages are entirelyindependl ent of the means for holding the nozzle in assembled relation,and which spacing means are not subject to change in shape or clearanceduring assembling operation, or cleaning.

Another object is to provide a spray nozzle assembly which may befabricated with a minimum of machining operations and in which thosemachining operations required are easily and simply made.

Another object is to provide a spray nozzle tip in which the means forproviding a vortical or whirling motion in the fluid passages are formedby straight cuts or shaping operations, thereby avoiding the expense ofconical helix generation.

Another object is to provide a tip for a spray nozzle that is separableas a unit from the body of said device, and which may be accurately andcheaply duplicated for quantity production.

These and other objects and advantages will be more fully apparent fromthe following description of a preferred embodiment of this invention,and from the accompanying drawing, which supplement the description andform a part of this specification. In the drawing:

Figure 1 is a longitudinal sectional view, to an enlarged scale, of aspray nozzle embodying this invention, and in which the tapered plugmember is crimped into place within the closure member.

' Figure 2 is a side elevation of the tapered plug member shown inFigure 1. 40

Figure 3 is an end elevation of the tapered plug member shown in Figure2, illustrating the angularly directed slots which give a vorticalmotion to the conoidal fluid jet.

Figure 4 is an approximately full scale side elevation, partly insection, showing an alternative method of assembling the nozzle tip tothe body, and also illustrating the nozzle assembly in place upon areceptacle from which liquid is to be withdrawn, mixed or diluted andatomized.

Referring to the drawing and particularly to Figures 1 and 4, the bodyof the nozzle is generally designated in, and in this example isprovided with an offset pressure fluid passage I I, extendinglongitudinally from a threaded inlet l2, to a recess or chamber I3. Asecond passage I4 extends axially partly through the body I0 andcommunicates with a threaded liquid inlet connection I5, which isillustrated as being on the side of the body I0. Bore I2 may beconnected to any fluid pressure supply, in this example a garden hose,and liquid inlet I5 may be connected by any suitable conduit to a liquidsource such as a receptacle for a concentrated spray material, as willbe more fully explained and described below.

A closure or cap I6 is secured to the outlet end of body I0 by means ofa threaded union nut I'I cooperating with corresponding threads I8 onbody I0. Closure I6 is provided with a tapered bore I9, whichcommunicates with a cylindrical outlet passage 20. The included angle ofthe bore I9 at the outlet and the angularity of grooves 26 have beenfound to be governing factors, and, when using water as a pressure fluidand aspirating and atomizing liquids, the included angle A of thetapered plug is preferably about 35 and the angle B between an axialline and each groove 26 is preferably about 15. With these dimensionsthe resultant angle C of the spray will be between 15 and 20 degrees. Agreater angle of spray will result from an increased value of either ofthe above angles A or B and will give poor aspiration. A smaller angleof spray gives poor atomization. Bore I9 is preferably finished by theuse of a tapered reamer, which permits accurate duplication with smoothbore finish.

A tapered plug generally designated 2I is mounted within the bore I9 ofcap I6, and the larger end of bore I9 may be crimped or beaded over asat 22 to hold the plug in place and aligned with the bore. This is aparticularly desirable construction if the nozzle tip is to be used in agarden sprayer, for example, where relatively unskilled operators maydismantle the whole device for cleaning. In case of oil burners and thelike, however, where skilled mechanics would ordinarily do this work,the crimping or beading is not required.

Plug 2I is illustrated in Figures 1, 2 and 3, and preferably comprises astem 23, of generally spherical shape adapted to seat into the bevelledoutlet 24 of liquid passage I4 in body ID. The major portion of plug 2I,however, is enclosed within bore I9 in cap IS. The base or skirt portion25 is of the same taper as bore I9 and fits it closely, therebyconstituting the aligning means between the plug 2I and the bore I9.Angularly directed grooves 26, best illustrated in Figure 3, andpreferably not less than six in number, are cut in the skirt 25 andserve to give the essential vortical or whirling motion to the pressurefluid passing around plug 2I. These grooves may be truly helical but ithas been determined that, if they are disposed as illustrated in Figure3, slightly displaced circumferentially from axial planes through plug2I, they may be made by a simple straight shaping operation,substantially parallel to the tapered outer surface of skirt 25, therebyeffecting considerable savings in machining costs.

Intermediate the ends of plug 2I may be located a circumferential groove21, which appears to act as an equalizing chamber, so that the fluidpassing outwardly between bore I9 and the tapered and inwardly spacedsurface of the plug tip 28 will be spread out as a smoothly flowingsheet instead of, for example, six independent streams from the sixgrooves 26 of the skirt. As just described, the tapered tip 28 of plug2| is. spaced inwardly by the lands 29 between grooves 26 from bore I9,preferably about 0.007 inch, plus or minus 0.002 inch, when using wateras a pressure fluid, and when aspirating and atomizing concentratedcommercial liquid insecticides.

The closure or cap I6 illustrated in Figure 1, is secured to the body IDby means of the threaded nut IT, as stated above, and the joint is madeliquid tight by a resilient composition or rubber gasket 30. The forceexerted by screwing nut Il onto threads I8 first compresses gasket 30and then seats stem 23 tightly into the bevelled outlet 24 of liquidpassage I4. This latter action forces plug 2I tightly into bore I9, ifit has not already been crimped therein as at 22, and the lands 29,contacting with bore I9 over their full faces and for a considerableaxial length, serve to perfectly align and space the tapered tip 28 inthe smaller end of bore I9. This arrangement completely eliminates anypossibility of misalignment of those parts, the threaded nut I'I servingonly to make tight the two fluid joints, at 39 and at 23, and to urgethe plug 2I and cap l6 into still more perfect union.

A strainer 3I may be inserted in chamber I3, or, as illustrated inFigure 4, may be placed in the bottom of threaded inlet I2, to preventdirt and debris from being carried into the grooves and passages of thenozzle tip.

As an alternative to the removable joining together of the nozzle tipand body by a union nut I1, as in Figure 1, the constructiondiagrammatically illustrated in Figure 4 may be employed, in which theclosure or cap I6 is flanged outwardly as at 32, and a correspondingflange 33 is formed on body I0. These flanges are preferably spacedapart slightly, as illustrated, by the stem 23 of the tapered plugseating in bore 24 (Fig. 1) and are enclosed and sealed by acircumferential ring 34, which is crimped or formed over the outer facesof the flanges 3| and 32. This obviously forms a tight and permanentunion between the body I0 and cap It, so that the desirable location ofwire mesh or perforated metal strainer 3I is at the bottom of threadedinlet bore I2.

Figure 4 also illustrates a. convenient arrangement of a receptacle 35as for a liquid insecticide, detachably secured to body I0 by a threadedcap 36, and into which a conduit 31 depends. The upper end of conduit 31com municates with the axial liquid inlet passage I4 of body I0(Figure 1) and allows liquid 39 to be aspirated from the receptacle 35,or, if the receptacle were to be inverted, permits the liquid to flow tothe axial liquid inlet I4, under a positive gravity head through axialbore 4I in plug 2| so that it passes into the converging jet of pressurefluid and is atomized into spray. My copending application above citeddiscloses means for obtaining a constant flow of liquid 39 fromreceptacle 35 in the position shown, regardless of the depth of liquidtherein, thereby providing a constant mixture-ratio with the pressurefluid admitted through hose 38 to the conoidal jet.

In operation, the pressure fluid, which may be water in the case of aninsecticide sprayer, or a gas such as air or steam in a burner nozzle,is admitted to body I0 through hose 42 threaded into inlet I2 and passesthrough bore II into chamber I3, from which it is admitted into theplurality of helical or angularly directed passages formed by thecooperation of grooves 26 and the bore I9 of cap I6. Thus the pressure 7fluid is given a whirling or vortical motion, which is preferablysmoothed out or made into a uniformly flowing sheet by circumferentialgroove 21 and finally passes out of the nozzle over the smoothly taperedsurface of tip 28. It will be found that the converging jet thus formeddoes not follow the cylindrical bore or outlet passage 26 of the cap [6,but leaves it cleanly at the juncture of 29 with the tapered bore I9.This action is facilitated by the projection of the end of tip 28 intothe cylindrical bore or outlet 28. After leaving the nozzle the streamerjet reaches a minimum diameter and then diverges again, forming theangle C (Fig. 4). It has been found by many tests that the angle C ofthe spray should be between 10 and 25 degrees, and, for best operationis substantially 15 degrees. This may be determined by several factors,the principal ones being (1) the included angle of the tapered tip 28and (2)' the vortical whirl produced by grooves 26 in skirt 25. If theangle of tip 28 is substantially degrees, the angle of grooves 26 withan axial line along the face of the skirt may lie between 13 and 16degrees for satisfactory operation. The extreme tip or end 48 of plug 2|is preferably flat or at least blunt, to facilitate the formation of areduced pressure in the axial bore at in said tip, through which latterthe liquid 39 from receptacle 35 or its equivalent may pass into theconverging conoidal jet of pressure fluid and be mixed and atomized inthe resulting spray.

Once determined, the clearances, concentricity and divergence of thespray are readily duplicated by the construction disclosed, and, what ismore important, these factors are not disturbed, as the plug 2! ma besecurely crimped into bore H), as disclosed above at 22, or, if notpermanently fastened therein, will be so accurately guided by the landsof base or skirt 25 contacting the bore 19 that misalignment is hardlypossible.

Although a specific example embodying this invention has been describedand illustrated, it is to be understood that the invention is notlimited to the particular features disclosed, and all such modificationsand changes as come within the scope of the following claims areembraced thereby.

2-. A spray nozzle comprising a body, a fluid chamber in said body, aclosure member for said chamber provided with a tapered bore, a taperedplug disposed within said bore, the base of said plug fitting said boreclosely and provided with substantially helical grooves and landsconstituting fluid passages, a circumferential groove intermediate theends of said plug, the remainder of the tapered portion of said plugbeing of smooth configuration and spaced from said bore solely by saidlands, and an axial liquid passage in said plug.

3. A spray nozzle assembly comprising a bod provided with a recess, afluid passage in said body communicating with said recess at one sidethereof, a liquid passage in said body coaxial with said recess andcommunicating therewith through a beveled seat, a tip for said nozzleconstituting complementary means for producing an annular uniformlyconverging conical passage communicating with said fluid passage, saidtip provided with an axially projecting member received in said beveledseat, said member and tip being provided with a passage coaxial withsaid conical passage, and means for securing said nozzle tip to saidbody.

4. In a spray nozzle including a closure cap provided with a convergingtapered bore and means for admitting a pressure fluid to said bore, atapered plug provided with a grooved base at its larger end, acircumferential groove intermediate its ends, and a smoothly taperedtip, said tip conforming to the taper of said bore and spaced therefromsolely by said base, and an axial bore in said plug.

GEORGE LEONARD NEELY.

